This sounds great!
I never got to reading manga on my Paperwhite 4(?) because the scaling made the text terrible to read (that was with KOReader a few years ago). Does this tool handle this better?
A recent feature I implemented a few weeks ago was virtual panel view.
You can enable it in the Kindle Aa menu.
You can double tap a corner to zoom into the corner in portrait mode 150% zoom.
Or you can turn the Kindle sideways to read half a page at a time.
and KCC scaling using the LANCOZ algorithm, which looks great.